Any system that does not use feedback

(transitive, intransitive) Used other than figuratively or idiomatically: see break, open. / To make a breakthrough on a mystery or problem; to cause a breakthrough to be made.

Third-person singular simple present indicative form of break open

Third-person singular simple present indicative form of lay open

the state or quality of being open-ended

to expand, to widen, to unwrap or unfold, to spread out from a compact state

(informal, computing) A programmer who works only on open source programs.

(clothing) Open at the neck.

(military) A military unit formed up so as to allow space between its ranks. / (nautical) A naval formation in which ships are four cables'-length (2880 feet) apart.

plural of open tuning